Magneto ignition device.



3 SHEETS-SHEET 1.

Patented 0G11. 14, 1913.

H. II. WIXON.

MAGNET() IGNITION DEVICE.

APPLICATION FILED MAR.4, 1910.

Inven DF Howard H. WIXnn 'A urne ggd W1 Deseas 2%7( @M7/M I H. H. WIXON.MAGNET() IGNITION DEVICE. APPLICATION FILED MAR.4, 1910. 1,075,531.Patented 0@t.14,1913. a SHEETS-SHEET z. l

. Inven nr award H. WIXnn E L '.qg/

A UFIIEHS WIIIESEES 4 @7% H. H. WIXON. MAGNETO IGNITION DEVICE..APPLICATION FILED MAR.4,1910.

Patented 0013. I4, l93.

3 SHEETS-'SHEET 3.

WIIHESSEE Howard #To all whom it may concern:

UNITED STATES Img lnrirA oEEIcE.

HowanD H. WIXON, OE CHICAGO, ILLINOIS, A'ssI'GNoR To s'rRoMBERG MOTORDEVICES COMPANY, OE CHICAGO, ILLINOIS, a CORPORATIONOE ILLINOIS.,

Be it known that I, HOWARD II'WYIXON, a citizen of the United States,residlng at Chicago, in the county `of Cook. and Statev of Illinois,have invented a certaln new and useful Improvement inv Magneto IgnitionDevices, of which the following is a full, clear, concise, and exactdescription, reference being had to the accompanying drawings, forming apart of this specification.

My invention' relates to v electric generators, commonly known asmagnetos, for the ignition of the combustible mixtures in gas engines,and is particularly adaptable for use in connection., with gas enginesem'- ployed for the `propulsion of automobiles.

The object of myinve'ntion is to provide a magneto-generator in/whichthe various parts are,arranged withgreat compactness,`V .presenting astructure occupymg a comparatively small amount of space withoutsacrificing anything in the line of eiiiciency, thereby securing manymechanical and electrical advantages.

lAmong the main features which characterize my invention may be herementioned: (1) a stationary induction winding having both primary andsecondary coils; (2) an interrupter so constructed that the primarycircuitis interrupted, first by one pair of contacts and then byanother, in order tov distribute the injurious effect of the sparkingamong the several contacts, whereby the life of the interrupter-contactsis greatly prolonged; (3) the provision of a rotatable I spark-gap inthe secondaryv circuit in parallel with the spark-plugs of thecylinders, this spark-gap constituting -not only asafety-gap but at thesame time performing the function of a testing-gap to determine therelation of the moment of sparking with respect to the position ofthecylinder-piston. readily understood by a consideration of the severalviews shown in the accompanying drawings, in' which:

Figure l is a longitudinal cross-sectional` view taken approximately online 1-1 of Fig. 2, 'certain of the parts being, for' the fsakeof'clea'rness, shown in full lines; Fig. 2 is a transversecross-sectional. view approximately on the line 2 2 of Fig. 1, certainofA Specification oLLetters Patent. Application led Hatch 4, 19 10.Serial No. 547,190.

Theseand other features will be" view of the upper portion ofthemachine, showing the distributer in place on the machine, certain of theparts being, for the sake of .clearness, shown in cross-section; Fig. 4isI a cross-sectional view, in plan, taken 'Online 4-4 of Fig. l, andshowing the interrupter casing in position -on the magneto; F ig.Y 5 isan interior view of the interrupter; Fig. 6 is a longitudinalcrosssectional view of'a portion of the armature shaft, showingfthelaminations in the shaft;

Patented oet. 14; 1913.

Fig. Tis an end view of the main framework. of the machine as detachedfrom the assoclated parts; Fig. 8 is a side view of the main framework,rand Fig. 9 is a diagram of the circuit connections.

Referring to Figs. r and 8, the main framework of the magneto-generatorcomprises a non-magnetic base-portion l, which, in practice, wouldordinarily be made of brass, a pair of magnetic side-portions 2 and'.

pairs ofpermanent horse-shoe magnets for A the field-magnets, but theprecise number of such magnets to be employed may, of course, be varied,depending upon the strength of the field whichit is desired to secure inany particular machine. The main framework has the cent-ralcylindrical-bore or space 5',

the sides of which formthe polar faces 6 and G. In this cylindricalspace within the `framework is arranged a stationary induction-winding7, comprising the inner vor primary coil S and the outer or secondarycoilv 9. Suitable insulation separates the coils from each other andalso surrounds the outside of vthe coils` as indicated cross-sectionallyin Fig. 1. This induction-winding is a unitary part which may be readilyinserted in place in the magneto andas readilyV withdrawn therefrom,after the other parts located in the cylindrical spacing have beenremoved, as will `hereinafter appear. The central ridge S onthe outsideof the windingis just sufficiently smaller in diameter than the space inthe framework to permit the wind- 55 of securing these`V`polar-extensions to the ving being inserted v'ithin the framework andheld stationaryy therein. In'order t'o properly guide'the Winding inplace when it is inserted wthintheA framework of themagneto, suitableguiding means .is provided, which, in the specific instance shown,consists of atlug 9,l carried by the'wind'ing and i -a cooperating oove9a provided at a suit,

able point on t e framework within the cy'- lindric'al space, asindicated in Figs.`2 and 7.-

Asa further locking means for the winding when in place, aspring-pressed lug 11 supported in the framework 4by the screw- Ithreaded'tube 1,2 is adapted to enter a recess 13 in the'peripheralridgerwof the'w'inding..

Uponwithdrawal of the windin the. yielding-lug 11 will be forced out .othe recess.-

i By thus. providing' guiding and locking means for the windingit'willalways be os-7 sible to lace the windin upon the mac line in exact y thesame positlon. This is impor- I tant whenit is considered that upon theoutside of the'wind-ing arelocated the terminals whichrare intended toengage certain' contact members, as .will-be described subsequently,

mounted at certain points on the machi-ne.

In order that the exposed terminals' of the coils of the inductionwindin may register withv the contacts carried byt e framework, it is,of course, necessary that the, position ofthe winding on the vmagneto bealways the same with respect to the contacts. This sameness of positionis insured by some such suitable guiding and locking meansas abovedescribed... I Passing axially through theA winding is llthe armatureshaft 10 v rotatably supported in'bearings 11 and 12. The bearing'll iscarried by the'rear end-plate 13Jsecured to the frameworkof the machine,while the bearing 12 is mounted in the supportA 14, held in the'fr'ontend-plate 15. Anti-friction rollers 1 6 and 17 workin the bearings-,11'

A... and 12', respectively. A- vpair ofv segmental i armature shaftatopposite ends of the windpolar-extensions 18 and 19 are secured to theing. In the particular instance illustrated,

the armature is screw-threaded at 20 and 2 1,

v,and the .polar-extensions gare mounted on these screw-threadedportions, locking screws 22 and 23 being' providedI yon. the

' polar-extensions to prevent accidental" disarrangement ofthepolar-.extensions 'afterI they have been `fastened in vposition on thearmature shaft. Any other approved means armature shaft may be obviouslyemployed,

although the screw-threaded engagement be! tween-theparts has the'advantage of readily permittin axial as well as radial adjustment of te polar-extensions onfthe arma- Ktureshaft The polar-extensions aswellas the armature' shaft are .of magnetic mate-` Ares rial-at least thatportion of the armature Shaft which is included between. theA polarorderto provide a large surface on the faces ofthe polar-extensions Ipreferably form the latter substantially as shown in Fig. 1, from whichit will be seen that the-polarextensions are lprovided with axialelongations 18 and 19', respectively, these elongations projecting intothe space 7 formed 'between the-winding and the surrounding 'surface ofthe main framework. By'this arrangement the length of the machine isreduced, since, if the elongations of the polarvextensions projectedoutwardly away from each other, .it would be necessary to lengthen thepole-pieces accordingly, or else materially reduce the length of theinduction-Winding, and thus reduce theefficiency of the machine. y Theoperation of the machine thus far -described will be apparent to thoseskilled in the art. As thearmature isrotated or oscillated the magneticflux of the field will be ,periodicallyl short-circuited through vthe vwinding, ir'st in one direction and then in the" reverse direction. Thisshort-circuiting of the flux takes place when the polarextensions aremoving .opposite'the polepieces, as indicated in Fig. 2, ^where thepolar-extension '18 is shown in a position from the position indicatedin Fig. 1.

iWhen the armature is in the position shown in Fig. 2 the'magnetic fluxwill pass, (as- .suming the polarities of the magnets ,as 1ndicated by Nand S),-from the pole-piece 2 into the polar-extension 18, through thewindingin a direction awayfrom the observer, returning way of. thepolar-extension 19 tothe opposite pole-piece 2.

When the armature lis in a position 180 from that indicated in Fig. 2,the magnetic fiux will be reversed through the stationary winding,passing from the pole-piece 2 rinto the polar-extension 1 9, through thearmature in -a direction toward the observer, and

returning throughthe(polar-extension` 18 y l into the south pole-piece2.

I.VVhenthe inductor is set in rotation an I lelectromoti've force isinduced in the Wind,

ing bytheaction of the field magnet. If

now the primary 'coil is short-circuited, the 'current flowingtherethrough generates lines "of magnetic force which largely`neutralize the existing magnetic field,-'-that`is, they'l .125 ismthrough the coil. As soon as the circuit force back or oppose a changeof Vmagnetin the primary is broken,'-the`counteraction yof the generatedopposing flux ceases." y Owing tothe change which therebyinstantaneously arises int-he number of the lines 13() tivelycoarse,and' comprises comparativelyy few turns. whlle the wire constitutingthe.

secondary coil is comparatively fine, and comprises a comparativelylarge number of turns, in order that the electromotive force Generatedin the secondary coil may be sufciently high to cause sparking atV thesparkplugs of the engine cylinders. matter of mere mathematicalcalculation to thoseskilled in the art, and no further eX- planation isnecessary here on this point.

The flux-carrying portion of the'arma'ture shaft is laminated at 10. inorder to obviate or reduce to a minimum the eddy-currents set up by theux variations.V This avoids undue heating of the armature metal andconsequent waste -of energy. The laminations lie, of course, in theplaneof the polarextensions of the armature, as indicated in Figs. 2 and 6.In ordertosacrice nothing of the rigidity of the armature shaft, onlythe major portion of the'latter is laminated,

the laminations 10 being secured in the cuti sist entirely lo awayportion `102. Of course, if desired, the linx-carrying 'portion of'theshaft may conto the solid end-portions of the shaft.

The armature shaft 10 has an extension 24, to which is rigidly securedthe arm-25, having at its opposite ends a pair of rollers 26 and 2Tpivoted at 28 and 29., respectively. These rollers are insulated fromthe arm by insulating bushings 30 and 31, as shownin Fig. l. This arm,with its oppositely-disposed engaging surfaces, shown as rollers in thespecific embodiment illustrated, constitutes the movable contact memberkof my interrupten Just how this contact ,mem-- bercoperates with thecircuit contacts of my interrupter is best illustrated in Fig.` 5, whichshows the various parts that go to make up my interrupter mechanism.VTol cally connected with "this support. The stationarv contacts 35 and36,are carried by metallic lugs 39 and 40, respectively, which lugs findbearing in the outer metallic platev 41. This outer plate constitutes acover for This is a.

lamin, and suitably secured the cylindrical support 32, and these two d`tively fixed contacts 35 and 36 are electrically connected in parallel.It will be` apparent from Fig. 5 that the rollers 26 and 2T of theinterrupter-arm are of'unequal size, so that the oppositely-disposed.engaging surfaces of this arm maybe said to be at unequal distances fromthe axis of rotation. The purpose of this arrangement is to cause theinterruption of the primary circuit. in which the interrupter isincluded, first by one pair of contactsand then by the other pair, inorder that-the burden of sparking may be distributed between the twopairs of contacts. lIt is clear that in this way the life of thecontacts is practically doubled, and the interrupter will enduresubstantially twice as long as it would if there were but a single pairof contacts for interrupting the primary circuit. If We assume therotation of the interrupter-arm` .as indicated by the arrow in Fig.l 5,it will be seen that the contacts 33 and 35 Will first be separated.However, this will cause no interruption of the primary circuit, for thereason that the circuit is still closed through the parallel path whichincludes the lother pair of contacts, namely, the contacts 34 and 36.roller'27 will come into engagement with the movable contact 34 andseparate the As the arm continues its rotation' the engine cylinder.A Asthe arm 25 continues..v

its rotation, the roller 27 willbe the first'to release its associatedlmovable contact,land the circuit lwill, be closed, almostinstantaneously after its interruption, through the contacts 34 and 36'.This will be followed in .Vj

quick succession by the closure of the parallel path which includes theother pairf of contacts 33 and 35. When ,the interrupterarm reaches aposition 180o from that shown in Fig. 5, it will be clear that thelarger roller 26 will first open the parallel path which includes thecontacts 34 and 36. However,l this will not rinterrupt the primarycircuit, because the circuit is still closed through the parallel pathwhich in`- f cludes the switch-contacts 33 and 35.` As.l

soon as the smaller roller 27 separates 'the contact 33 from the contact35 (whichwvill, of course, take place while the contacts 34 and 36 areheld separatedby the roller 26)',

the primary circuit ywill again inter- "across the contacts 33 andrupted, and whatever @parking will take place at this moment ofinterruptionwill be By thus y causing interruption of theprimarycircuit,

first through' one pair of contacts and then through the other pair, thelife of the interruptei' is practically double that of. thoseinterrupters in which but a single pair of contacts is employed.securedA by so arranging -the two pairs o'f contacts and theinterruptor-arm that the.

. cyclical actuation of the contacts takes place in succession, thecircuit` being interrupted alternately by one pair andftlien the othei'pair of contacts. i

In order that the interrupter-casing may be readily attached to themagneto Y'and as readily removed therefrom, a bearing-plate I43 isrotatably mountedin'tlie front endplate 15, as `shown in Figs. 1 and `4.

Through the opening 44v.in thisbearing ings 52,' aS best -seen in Fig.v4. Into the. openings 54Y extend the projections or buttons 55, whichare pressed outwardly by suitable springs 56. 'lien it is desired toinsert the interrupter-casing in placev on .the

magneto, Uit is only v'necessary 'to bring the openingsl offtliecasinginto alineinent with the lugs 45 and 46'land press the casing inwardlyuntil the parts are in the position shown in- Fig. 4, when thebuttons57i-will i'estin the grooves of the head-portions 47 and 48 of the lugs45and 4G. This produces a separable locking engagement between therotatable base-plate 43 and the yinterruptercasing. As shown in Figs. 1and'4, the front end-plate 15 1s provided with a circular shoulder l5,which forms a housing for the y interrupter casing. yAn insulating disk57,

preferably securedto the base-plate 43, in-

y sgilates the latter-from the cylindricalv supshown in Fig. 4. Thisbinding-post makes This is diagrammatically indicated `in Fig.,

port 32 of the vinterrupter-casing. From this it'will be seenthat thestationary contacts 35 and 36v are grounded to the magneto, while themovable contacts 33 andy 34 are insulated therefrom. The binding-post 58is carried by the end-plate 15 and insulated therefrom by aninsulating-bushing 59,A as

electicalcontact withthe cylindrical support' 32, and therefore with themovable contacts 33 and `34carried -byj said support.

And this advantage isV The coverl9, Whiehialsoshows the stationarycont-acts y 35 and 36 grounded to the machine at G.

The detailed description of this figure will be taken up later on in duecourse. The objectvof having the interrupter radially adjustable is tovary the moment of sparking with respect to the position of the enginecylinder; Since'the 'armature shaft is driven by the engine, and sincethe interrupter-arin 25 is driven by the armature, it will be lapparentthat by rot-atingI the yinte-rrupteicasing the moment at whichtliecircuit will be interrupted one of the pairsof contacts may beVaried;with-respectl to the position of thel engine cylinder, or (whichamounts tothe same thing) with respect to the position of the armature.In order to vget the best sparking it is customary to so time the momentof circuit-interruption that it will occur snb's'tantiallyat the momentof generation of maximumeleetromotive force, 'which (as is Well known)takesplace when the armature is about to interruptrthe magneticshort-circuit throughftlie inductionwinding, or-at least reduce itto aminimum. In my magneto this will take place when the armatureissubstantially inthe position in l which itis shown 1n Fig. 1, or v1n aposition 180 therefrom. In order to facilitate the v adjustment of theinterrupter-casing I havev Vprovided an arm '60, arranged at.rightangles to the bar 53 and`removablyattaclied to theinterrupter-casing in any A suitable manner. In the presentinstance thecoverplate 41 of theinterrupter-casing carries a pair of'lugs 61', whichenter openings 62 inthe arm'60, the spring-pressedfbuttons G3 providinga, separable locking engagement i 'between'` the two parts. The aim (S0has an extension 64 provided with an opening 65 to afford connectionwith the timing level' ofl the nautomobile equipment, or with some othersuitable part which the driver of the machine may conveniently 'operateto adjilst 1 the time of ignition.

I come now to the distributer which forms part yofthe' magneto outfit.vFor the sake of illustration, ithas been assumed that the preciseembodiment of'my magneto-generator illustrated in tlie drawings is ,fora four-'cylinder engi-ne, and, therefore, the distributer is shown asprovided with four contacts 6G, 67, 68 and 69 mounted in the insulatingring 70.' Each Contact is cleo-` trically .connected with acontact-terminal 71 by .conductor 72. From the terminals 71 connectionslead to the spark-plugsof the engine cylinders. protect. the upperportions fof the contactterminals 71. The supporting-ring 70 and theAcontact-terminals 71 arecar-riedby a base-plate 74 of'insulatingmaterial. i A correspondingly=shaped cover-plate 75,-also of insulatingmaterial, is arrangedfto fit over the base-plate 74, as indicated inFig.'v 1, to

Insulating thinibles 73a inclose the parts and thereby.. protect themfrom liability to injury. Screws 76, passing through openings T7 in thebaseand coverplates, secure what may be termed the stationary part oftle distributer to the endplate 15.` 'ithin the cylindrical space 78,formed b v the ring 70, moves thev annular member T9 of insulatingrmaterial. A glass or mica-plate 80 carried by the cover 75 isprovidedjin front of the cylindrical space 78. The member 79 has ixedlymounted thereon the metallic arm 8l, which terminates at its outer endin an arc-shaped engaging surface 82, forming part of the periphery 83of the annular member 79,'as best shown in Fig.'3. At its inner end themetallic arm 81 is in electrical contact with extension Stof the shaft85.4 .It is on this yextension 81 that the annular member 79 is suitablysecured, as by screw-threaded engagement. An insulating-bushing 86 isfixed upon the member 79 by having itsshank portion 87A-inserted in anopening 1n the annular member, as cross-sect-ionally shown in Fig. l.The fron-t portion-of the bushing 86 serves to cover up the arm 81. Thisbushing 4carries spark-electrode 88, whose shank portion 89 has electricconnection with 'the metal disk 90, 4whichis preferably fixed to theinsulating member 79.

The projection 91 ontheextension 84 co.

operates with the electrode' 88 to form a spark-gap. how this spark-gapforms a combined safety and testing spark-gap. For the present let usproceed with a `description of the remaining structural features of mymagneto-l generator. The shaft 85 is housed lWithin the insulatingitube92, which may, in actual practice, be perhaps preferably constructed' oftwo parts, fitted into each other as indicated in Fig. 1. Thescrew-threaded end 973 of the shaft 85 is inserted'in a thimble 94,

which isix'ed within the tube 92. A me! tallic contact-ring 95 ismounted upon the tube 92, and electrically connected .withthe shaft 85by a conducting-pn-96. A metal 4tube 97 is fitted over oneend oftheinsulating tube 92 to provide support for the raceway 98, in which arelocated the rollers 99 y which work Iin the bearing-ring 100. This ringis supported in the' recess -portion 101 ofathe end-plate 15. From thisit will be seen that the electrode 88 is electrically grounded totheframework of the machine through the "disk 90, the metallic tube 97,against which the disk 90 abuts. and through the roller-bearingjustdescribed. VThe other electrode v91, on` the other hand, haselectrical engagement with the metallic rin 95, which Fis insulated fromthe framewor of f the machine. The other end portion of the insulatingtube 92 is connectedl with the metallic shaft 102,'having a recess 103into which extends the reduced portion v104: of

I will subsequently explain the tube 92. A,pin 105 is inserted throughthe parts to prevent relative rotation thereof. At an'intermediate pointtheshaft 102 has mountedy thereon the race-way 106 for theanti-friction'rollers 107, which workin the bearing-ring 108.,Thisringiis mounted in therecessed" portion 109 of t-he bearing-` plate1-10. The end-plate 13' and the bear' ing-plate 110y are recessed toformv ajhousing 111, in which is located the large gear 112 -fixed uponthe. end of the shaft 102. The

metal shaft 102, the insulating tube 94, and

the metallic tube 97 may be said to constitute l asfa: whole thedistributer-shaftwhich operates the annular member 79. A gear 113. fixedupon the armature shaft is'` in mesh with the gear 112, thuscommunicating the rotation of ,the armature shaft to the dis-vtributer-arm 81I and to the movable sparkl gap formed by the electrodes88 and 91 which move in synchronism with the distributerarm. Thevgear-ratio between the gears 113 and 112 is such that the gear 113makes two revolutions to every revolution of the gear- 112.' As thedistributer-arm 81 is rotated its engaging surface 82 makes'elec--trical ,contact with the projecting points 114 of the contacts 66, 67,.68 and 69. Preferably, these projecting points, or buttons, as

they `might 'be termed, are vmounted resiliently, so that good contactmay be Vinsured between them and the distributer-arm 81.n p

Referring to Fig.. 8, the` cutaway portions 115 and 116 at opposite endsof the top member 3 are for the purpose of accommodating the recessed`portion 109 on the roc bearing member 110 and the recessed portion 101on th`e front end-plate 15. Besides the insulating-block has mountedtherein the contact-button 122, which is pressed against thevcontact-ring 95l by` the spring 123.' Through this spring thecontact-button has connection with an outer contactfvbutton 124,

which is adapted to'make electricalengagewinding 9, as diagrammaticallyindicated in. Fig. `2. )It will therefore be seen that thedistributer-arm 81, as Well as thefelectrode 91,1,are velectricallyconnected with'the ter- `minal 125 of the secondary ,winding 9. Thisconnection, which has yalready been describedstructurally in connectionwith Fig. 1. is diagrammatically -indicated\by-the` conductor v126 vinFigri'9. i The insulating-block also carries the contact 127, which isnormally pressed outwardly by the spring `128 `located in a' recess intheinsulating-block.

vment with the terminal 125 of the'secondary the primary winding 8, asindicated diagrammatically in Fig. 2. The binding-post 130 is forconnection with one terminal of the condenser 132. convenientlysupported within the magneto on the top member 3. In the diagram of Fig.9, the conductor 133 i represents the connection between thebinding-post 1,30 and one terminal of the con.

' denser, while the conductor '134 represents the connection between thebinding-post 130 i and .the terminal 131 of the primary winding. In thebottom ofthe base-portion 1 is secured the contact-terminal 135insulated from the machine by the insulating-bushing 136.k VThe objectof this contact-terminal 135 is to make connection with` the terminal131 of theprimary winding throughthe conductor 137, as diagrammaticallyindicated in Figs. 2 and 9. The lterminals 135 and 58 `are adapted to beelectrically connected, and this connection is diagrammaticallyindicated in Fig. 9 by they conductor 138. Inasmuch as thecontact-terminal 58 is electrically connected` with "the movablecontacts 33 and 34 of t-he interrupter, it is apparent that thecondenser 132 isfconnected in parallel with the interrupter. Referringagain to Fig. 2, the lother terminals of the primary and secondarywindings are grounded'to the machine, as diagrammatically indicated at139.- In the actual construction of the induction-winding, theterminal-conductors 125, 131, 137 and 139 are preferably made of flatribbon, and terminate in fixed positions on the peripheryl of y 'theinsulation which covers theY winding.

It will now be appreciated -why it is necessary that the armature bealways inserted .on the magneto in a predetermined. position. So far asthe grounding-terminal 139 is concerned, this would make contact withthe metal of the machine 1n various posi- .tions of the armature, butthe terminal-conductors 125, 131 and 137 mustffall in place opposite thecontacts 124, 127 and 135, respectively. This registering of theterminalconductors and the contacts is` insured by `the guiding meansfor thearmature, as previously explained. y

There remain to be described the `circuit connections shown in thediagrammatic View of Fig. 9, together with the operation of thesystem.Most of the parts shown in Fig. 9 have already been referred toinconnection with the description of certain structural y features of mymagneto. In order, however,

to complete the description of what is shown in Fig. 9,' I will add thattothe common I groundiG, which may be said "to represent the metal o themachine, are connected the otherI terminalvof the condenser by theconductor 140, the other terminals of the primary andsecondary. windingsby the conyductors`141 and 142, respectively, and `the 'stationarycontacts 35'and 36 by the conductor 143. The ground for the electrode 88carried by the movable member-of the distributer'is indicated at 144.-'The distributer contacts 66, 67, 68 and 69 are connected by conductors145, 146, 147 and 148, respectively, to the electrodes 149 of thesparkplugs. The other set of electrodes 150 is connected to ground, asindicated lat 151. Therparallel connection of the movable contacts 33and 34 of the interrupter is indicatedby thesring-conductor 32', whichis supposed to represent diagrammatically the cylindrical support 32 onwhich the movable contacts are mounted. The conductor 152 represents theelectrical connection between the bindingJpost 58 and the cylindricalsupport indicated diagrammatically by 32. The parallel connection of thefxedfcontacts 35 and 36 is indicated by the. conductors 153 and '154,which are connected tothe com-` mon conductor 143. It will be apparent,from a considerationfof the circuit arrangement shown in Fig. 9, thatthe condenser is connected in parallel with the interrupter,

that the pairs of interrupter-.contacts are connected in parallel witheach other, yand that the electrodes 88 and 91 are arranged in parallelwith the electrodes of the cylinder spark-plugs. The, object of havingthe condenser in parallel with the interrupter is, as is well known bythose skilled in the art, to prevent as-much -as possible the sparkingat 'theelectrodes which interrupt the yprimary circuit, and alsotofincrase the` voltage in thersecondary circuit. by accelerating theflux variations through the induction-` 'windingz I have previouslystated that the electrodes 88 and 91 constitute a combinedv safety andtesting-gap. How they constitute a safety-gap .is apparent from thefactthat these electrodes are 1n parallel with the i electrodes of thespark-plugs, so that if for any reason the current should fail" to leapacross the electrodes of the spark-plug which the distributer hasconnected in the circuit of the secondary winding, the secondary currentsurging through the secondary circuit under high pressure would leapacross the spark-gap formed by the terminals 88 and 91., thusdischarging the sec ondary circuit with safety.

the electrodes 88J and 91 is brought about by the fact that thespark-gap rotatesin unison i with the distributer-arm and in alinementOtherwise,- there would-be danger of the secondary`Y *netic iiux throughsald winding, an intertherewith, so that by disconnecting a cylinderspark-plug from the distributer and operating the magneto the positionof the 'spark that will pass across the electrodes 88 and 91 willindicate at what position of wthe engine-piston the moment of sparkingis occrring.l If thejsparking is too early or l tage an my invention,

too late the interrupter may be readily adljustedV inthe mannerpreviously described. Of course. it is vobvious testingap does notdepend for itsadvan- 'utility upon the other features of and I thereforeclaim the same broadly. Similarly does lmy novel form ofl interrupter`not depend for its utility upon the presence of the other features of:my invention herein described, as will be apparent from- 'certain ofthe appended clalms.

Having thus-'described my invention, what I claim as. new and desire tosecure by Let- ,ters Patent of the United States is:- 'n

i 1. In a` magneto-generator, ,a non-magnetic base-portion, .a pair ofmagnetic sideportions secured to said base-portion and formingpolepieces, a non-magneticy top'- portion secured .to saidf pole-piecesand provided .with a longitudinal opening, said four portionsconstituting a hollow frame-work, magnets incontact with saidpole-pieces, a stationary` lgenerator winding .arranged -withinsaidframework, an unwound armature'rotatable within said framework andhaving extensions passing over the periphery of the winding'forreversing '.the'magrupter carried onthe framework 'at one end andoperated bythe armature shaft, a distributer alsoc'arried `on theframework at the same end, an operating shaft for said distributerpassing through the opening in the top-portion' of said framework, and agear connection between said two shafts' at i thel other end of suchframework.

\ A2.In a magneto-generator for ignition purposes, the combination of aframework,

magnets supported thereby, a pair' of end'- plates secured tosaid'framework, a distrib# uter and an interrupter mounted one above theother uponl one of said end-plates, a

generator f winding between said magnet ends, a rotatable armaturehaving extcn winding 'for reversing the magnetic fiux winding disposedtherein, a rotatable armasions -passing over the periphery of thethroughsaid winding, a shaft on which said armatnre ismounted, saidshaft operating the interrupter, a second shaftfor-'operatingthe-distributer, and gearing at the other end-plate for connecting' saidshafts together. A N

f 3.- In a magneto-generator, the combination of a magnetic field-frame,ageneratorture for reversing the magnetic-flux through said winding, ashaft for said armature that this rotatable journaled vin theends ofsaid Held-frame, a

radial arm securedto one end of said shaft, a plurality of 4contactsdisposed in proximity to said tacts are mounted to be actuated by saidarm, a rotatable base-plate carried by the arm, 'a' casing in whichsaidconfield-frame Vconcentrically withthe armature axis, and means forsecuring locking engagementl between said casing and said base-platewhen the casing is placedin position on the magneto, said meanspermitting ready removal fromthe casing.

4. In a magneto-generator having a fieldyframe, a generator-winding andan armature, the combination of a rotatable baseplate mounted in one endof thefield-frame concentrically with the armature axis,' ay

pair of lugs extending axially from said base-plate, a cylindricalcasing provided with`openings for receiving said lugs when the casing isinsertedin place on the magneto, whereby engagement isxsecured betweenthe casing and the base-plate .to permit radial adjustment -yof thecasing and ready removal thereoffrom the magneto, a plurality ofcircuitecontacts carried by said casing, and an interrupter-arm operatedby the. armature shaft for actuating said coni tacts.

45'. "In a magneto-generator, a, non-magnetic base-portion, a pair ofmagnetlc Sldeportions secured to said base-portion and formingpole-pieces, a non-magnetic topportion secured to said pole-pieces andprovided with a longitudinal opening, said four portions constituting ahollow framework,

-magnets in contact with said pole-pieces, a

block and having connection with said windi ingfa contactring mounted onthe insulated portion of the distributer-shaft and connected with ametallic portion thereof, said contact-ring engaging one lof saidContact v members, and a gear connection between said shafts. I

6,y In a magneto'generator, a field frame,

a stationary gemerator winding arranged within saidframe, an unwoundarmature rotatable within sald frame and havlng eX- tensionspassing'over the periphery 'of the e winding ffor receiving the magneticflux through said winding, an interrupter cara stationary generatorWinding 'arranged' .within said frame, an unwound armature rotatablewithin said frame'and having extensions passing over the peripheryof-the winding for receiving lthe magnetic ux through said winding, aninte'rupter carred on the frame at one endand .o'erated by the armatureshaft,`a distributer a so carried on` the frame at .the same end, anoperating shaftv for `said distributer lpassing through an opening insaid frame, and a 15 gear connection between said tw'o shafts attheother end of said frame. In witness whereof, I hereunto'subscribe`niy name this 1st day of March, A. D. 1910.

i HOWARD H. IVIXON. IVitnesses: i' f -y CHARLES A. BROWN, l

A. A. THOMAS.

